The invention relates to a micrometer screw gauge which is designed or used for setting or measuring longitudinal dimensions.
Micrometer screw gauges are used, for example, as external micrometers for the accurate measurement of diameters or other one-dimensional dimensions, and for the measurement of the size of the screw thread and the like. To do so, the external micrometers comprise two measuring screws defining between them a distance, at least one of said measuring screws being supported in a movable manner. An inertia drive can be used to change the distance between the two measuring screws, while a distance change is registered by a measuring system.
As a rule, the faces of the micrometer screws are cut to fit flat or are provided with a device for holding and tensioning gauge slides. These gauge slides, for example, comprise balls, blades or other specially configured surfaces for measuring specific workpiece profiles. For example, for screw thread measurement, blade-like gauge slides are known, whereby these slides need to be adapted to the specific screw thread. They are used for measurements between convolutions and rest against the flanks of the screw thread.
In this instance, the measurement is inconvenient when the measuring screw turns during its axial adjustment. Furthermore, a rotation of the measuring screw may result in the wear of the face of the measuring screw, in particular, if said face is brought into contact with abrasive material. For example, if abrasive materials are measured, this results in an undesirable wear when rotating measuring screws are used. Even the most minimal damage to a surface can result in measuring errors. Also, a rotating measuring screw can be inconvenient when sensitive materials or surfaces are measured or tested. For example, any sharp edges of a measuring screw can leave marks on brushed or otherwise visually appealing surfaces, or can damage sensitive surfaces, for example, varnished surfaces, soft surfaces or the like, with small cuts. This, too, is unacceptable.